Update for app framework removal

Changes:
- Remove the autobuild scripts and config.xml used by the app
  framework widget build.
- Update the qmake files to just build a "hvac" binary and install
  it into /usr/bin by default.
- Remove the code in main.cpp that handled reading the WebSocket
  command-line arguments and passing them to binding related
  code.
- Add setenv of QT_QUICK_CONTROLS_STYLE to "AGL" to get the AGL
  styling used.  This replaces a global environment variable
  definition tied to the old app framework, and makes it more
  obvious that the style is required for the app to properly
  work.

Bug-AGL: SPEC-4182

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: I6634a611741b442597dca2978a8dd0a6b6b75341